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With others, you can protect homes from wildfire

As human population in the high-hazard ‘red zone’ skyrockets, researchers strive to understand when these homeowners perceive wildfire risk and act to mitigate it

The fight against fires begins before the first spark—when homeowners in the wildland-urban interface choose whether to remove trees and bushes near their homes. What causes landowners to perceive risk and, further, to try to reduce the risk is not fully understood.

But Hannah Brenkert-Smith, a research associate at the University of Colorado Boulder’s Institute of Behavioral Science, is working to change that. She and her colleagues are studying the beliefs and behavior of homeowners in the forested “red zone”—the so-called wildland-urban interface where wildfires can destroy homes and other private property.

Understanding when and why mountain residents work to make their homes “firewise” is increasingly important. A Colorado State University study predicts that the number of homes in the red zone will increase from 300,000 in 2000 to 720,000 by 2030. Also during that time, the number of acres in the red zone is projected to rise from 715,000 to 2.6 million.

Brenkert-Smith is collaborating with Nicholas Flores, CU-Boulder professor and chair of economics; and Patricia A. Champ, an economist with the U.S. Forest Service’s Rocky Mountain Research Station in Fort Collins.

Some things are becoming clear. The team has found that while there is a wide variety of information about wildfire available, information shared by experts and non-experts correlate with higher perceived risk. Residents whose neighbors’ vegetation looks dense perceive themselves to be at higher risk.

Importantly, WUI homeowners are not a cohesive group that can be expected to make the same kinds of decisions.  For example, older-residents and women are more likely than others to undertake fire-mitigation work on their property.

As a doctoral student at CU-Boulder in 2003, Brenkert-Smith began interviewing and surveying red-zone residents after the devastating fire season of 2002.

In the decade since, researchers have focused more attention on wildfire’s social-science component, which has not been studied as extensively as that of natural hazards like earthquakes and floods.  Prior to the early 2000s, the population at risk of major wildfire losses simply wasn’t as extensive as it is now.

Besides the population increase in the red zone, generally drier and warmer climate increases wildfire risk; fire seasons are longer, and both fire frequency and severity have risen, especially in the West.

Land-management experts understand the dynamics of the natural world—accumulating fuel and changing climate. As Brenkert-Smith observes:

“The fire-science people have that all mapped out very neatly, but there was little understanding of what the people who were living in these areas were doing about the risk: if they recognized the risk, if they were concerned about it, what actions they would be more willing to take than others, what factors they were grappling with when they were making decisions.”

As the red-zone population and at-risk property increase, homeowners in fire-prone areas represent an increasingly important group whose actions affect the likelihood of major fire losses.

So Brenkert-Smith and her colleagues surveyed a random sample of households in the red zone in Boulder and Larimer Counties.

The team drew upon its own qualitative research results and major findings from natural-hazards research. “We wanted to understand the whole field of decision-making,” she says.

One aspect of the research involved asking homeowners to specify which, if any, efforts they’d made mitigate the danger of fire to their homes.

The team’s survey also asked about a range of demographic information, plus about each homeowner’s perception of risk, and sources of wildfire risk.

The team found a correlation between fire-mitigation efforts with those who had received fire-mitigation information from local experts such as local fire departments and county wildfire specialists.

Non-experts also seem to make a positive difference, Brenkert-Smith’s team found. “Talking with your neighbor about wildfire risk was really important in terms of mitigation outcomes.”

These findings mirrored the results of research into the role of social interactions in mitigating danger from other natural hazards.

Natural-hazards research has found that the specific risk people face is less important than social factors in predicting how people will respond to the risk.

Social scientists hypothesized that the same patterns seen with earthquakes or flooding would be seen with wildfire. “But here, we’re beginning to fill in that picture and confirm, yes, we’re finding some of the same patterns.”

Expert information sources and receiving information in formal social gatherings were important for the perceived probability of experiencing a wildfire. “Talking about fire, whether it’s with an expert or with your neighbor, increased the perceived probability of a fire occurring.”

This is important, Brenkert-Smith notes, because the federal government emphasizes community-level fire-mitigation programs. Such programs are based on the assumption that the social interactions galvanize increased risk perception and mitigation, but the mechanisms of how the interactions achieve these ends are largely undocumented, she adds.

While the assumption might prove to be true, researchers like Brenkert-Smith want to find the evidence so that the social mechanisms at work, how they work, and the varied outcomes are better understood.

A slurry bomber drops fire-retardant near a home engulfed in flames as firefighters scrambled to control the Fourmile Fire in 2010. Researchers say that events like this heighten the perception of “red zone” homeowners that their property could be at risk and could prompt many of them, particularly longtime homeowners and women, to undertake fire-mitigation efforts. Photo courtesy of Boulder Daily Camera.

After the 2010 Fourmile Canyon Fire, Brenkert-Smith’s team sent a follow-up survey to Boulder and Larimer County residents who had previously participated in the survey.

Though the researchers are still studying the results, some things are clear: Risk perception has risen. However when perceived probability and consequences are examined separately it appears that homeowners’ expectations regarding wildfire consequences (e.g. trees burning, damage to home) have increased while expected probability of a fire occurring does not change between the two surveys.

Homeowners are doing more mitigation on their properties.  Additionally, homeowners are more likely to identify vegetation on their own land as a source of risk for them. That is significant, because homeowners who understand the risk are more likely to try to reduce that risk.

Brenkert-Smith, Flores and collaborators at the National Center for Atmospheric Research recently won a $298,000- research grant from the National Science Foundation.

The project, called “Assessing the effects of risk interdependency, social norms, and costs on homeowners’ wildfire mitigation decisions using choice experiments,” is a first of a multi-phased project on Colorado’s Western Slope examining homeowners’ social norms, costs of mitigation and “risk interdependency.”

In the red zone, risk interdependency is the extent to which a landowner’s fire-mitigation action or inaction affects not only her or his own parcel but also adjacent land, and vice versa.

The researchers will provide scenarios with varied conditions and ask residents hypothetical questions about whether they would undertake fire mitigation if they perceived danger on neighbors’ land, if most neighbors were clearing trees and brush, or if they had enough money to do fire mitigation.

Sen. Mark Udall, the Colorado Democrat, recently heralded the new study:

“Wildfires are an unfortunate part of life for many of us living in Colorado. However, there is much homeowners can do to prepare their properties and reduce the risk that they or their neighbors will lose a home or loved one in a fire,” Udall said.

“This competitive grant is welcome news for the millions of Coloradans who live in and around our fire-prone areas. I look forward to seeing this study’s conclusions and how we can better encourage homeowners to create defensible space around their homes.”

By introducing varied scenarios and hypotheticals, the researchers can pull questions “out of the messiness of real life” in order to better understand how some fundamental aspects of decision-making interact , Brenkert-Smith said.  “Ultimately, the goal is to put it right back into the messiness of real life.”